Hi Larry!

Was not quoting Art here, although he mentioned to me verbally that he
has used full back yoke to rotate, especially with the heavier
engined cherokees and the "full fuel, 2 heavy front seat Pilot/pax
and no baggage" situation....

I had it well back, but have not hit the stop yet, and may never.

Apparently, if done to soon, the aircraft simply won't lift...

Although having spoken to several about this mod, I was only
slightly prepared for the result..

Now, remember, it was cold, slight head wind, and I was light.

Brakes held , full RPM, and let go....

I was well in the air at the 500 ft marker..

The deck angle was ...umm... "interesting" .

And the little Warrior just wanted to keep going up... no wobbles, no
stall warning, no buffeting, just the most rapid "up" I have ever
experienced with 150 horses...

Over a year ago. I got an E-mail from a straight wing Cherokee pilot
who indicated that these two mods are " the FIRST ones to spend money
on " when it comes to the Cherokees. He said he lowered his stall
speed by 7 mph.

I was doing 45 deg "S" turns at 45 knts indicated (at altitude)
easily. Lots of protest from the horn, but solid, no buffeting....

We have it at 4 knot difference so far, maybe 5..

One of my partners frequents a 1600 ft strip near his parents home. We
thought the extra margin would be a good investment.

More testing to come.. Will post results here if anyone interested.

Cheers!

Dave ...


On Wed, 03 Jan 2007 15:25:04 GMT, Larry Dighera
wrote:

On Wed, 03 Jan 2007 14:24:15 GMT, "Steve Foley"
wrote in j0Pmh.2$5g.0@trndny01:

I think he's referring to Art Mattson's high performance take-off procedure
for Cherokees.

See http://www.pipermods.com/

Dave must have some information additional to that provided on the web
site, as is see no mention of moving the elevator to the stop at
rotation:


http://www.pipermods.com/shortfield.htm
Short Field Takeoff Procedure
Getting the best short field performance out of your Cherokee begins
before reaching the end of the runway. This requires leaning to
slightly rich of max. power at your runup. This is achieved by leaning
to maximum static RPM and then richening the mixture slightly as you
would at your cruise altitude. (If you plan to cruise more than 2000
AGL, you will need to further richen the mixture.)

Never stop on the end of the runway. After you are cleared for
takeoff, make a rolling turn onto the runway-no flaps. When you reach
an angle of 45 deg. to the runway, start accelerating so that by the
time you have completed your turn, you are at full throttle.
Accelerate to your predetermined rotation speed (this is between 45
and 60 mph depending on mods, temperature and loading), at this speed,
pull in 2 notches of flaps, count 1.... 2 and rotate! You can take
your first notch of flaps off fairly soon after gaining some speed and
take the second one out as you continue to gain speed.

This procedure is like adding 300ft+ to the runway which reduces your
"pucker factor" for clearing obstacles. Practice on a longer than
needed runway and get comfortable with it before doing it on a short
field. I use this procedure on all takeoffs regardless of runway
length, as I go into short grass strips regularly and want the
procedure to be second nature. By using ths [sic] procedure, you will
quickly discover that your Cherokee is capable of more than you
realized.

For a first-hand account of how well this works, read Jim Cavanaugh's
article from Pipers Magazine.